Garlick Helicopters INC UH 1H accident near Cove, Oregon, May 31, 2015
On May 31, 2015 at about 6:26 pm local time, a 1965 Garlick Helicopters INC UH 1H, registered N462CC, was substantially damaged in an accident during maneuvering (low-alt flying) near Cove, Oregon. It was an external-load flight under external-load helicopter rules (Part 133). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The failure of the engine-to-transmission drive shaft coupling assembly due to a fatigue fracture of one of its attachment bolts, which resulted in a loss of power to the main rotor.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 31, 2015 · about 6:26 pm local time
- Place
- Cove, Oregon · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Garlick Helicopters INC UH 1H NO SERIES, built 1965 · all UH 1Hs on the register
- Registration
- N462CC · registry record · serial 6509666
- Damage
- Substantial damage
- Flight
- External-load flight · external-load helicopter rules (Part 133)
The NTSB's narrative final · quoted from the NTSB record
The commercial pilot reported that, while maneuvering the helicopter at low altitude during logging operations, he felt a vibration and heard a howling sound coming from the transmission area. He immediately initiated a precautionary landing; however, as the helicopter settled to the ground, the main rotor rpm dropped, and the pilot attempted to cushion the landing with aggressive collective input. The helicopter subsequently landed hard. Postaccident examination revealed multiple fractures of the Kaflex engine-to-transmission drive shaft coupling assembly. According to the flight manual, a failure of the engine-to-transmission drive shaft would lead to a complete loss of power to the main rotor. The coupling assembly failure was initiated by the failure of an attachment bolt due to a fatigue crack on the flange section that attached the coupling assembly to the transmission shaft flange. No evidence of any material anomalies were found in the fractured bolt, and the fatigue crack was likely caused by the severe stress imposed by logging operations. The manufacturer did not specify a replacement interval for the bolt. The investigation could not determine when the fatigue crack developed and propagated; therefore, it could not be determined whether the crack would have been identified during an annual inspection.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Powerplant sys/comp malf/fail during maneuvering (low-alt flying) defining event
- Hard landing during landing
The NTSB's findings
- cause Aircraft › Aircraft propeller/rotor › Main rotor system › Main rotor mast/swashplate › Failure
- cause Aircraft › Aircraft propeller/rotor › Main rotor system › (general) › Fatigue/wear/corrosion
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: helicopter; instrument: airplane; rotorcraft: helicopter
- Flight time: 13,896 hours in all; 883 in this make and model; 69 in the last 90 days; 23 in the last 30 days; 13,800 as pilot in command; 2,200 on instruments
- Last flight review: December 28, 2014
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 7,598.6 hours
- Last inspection: annual inspection, March 27, 2015
- Maximum gross weight: 9,500 lb
- Seats: 2
- Landing gear: fixed
- Engine: Lycoming T53-L-703 (turboshaft); 3,064 hours total
The flight
- Departed from: Cove OR at 6:00 pm
- Destination: 7OR0 Cove OR
Weather at the time
- Light: daylight
- Wind: from 190° at 9 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 77°F (25°C), dew point 48°F (9°C)
- Altimeter: 29.79 inHg
- Observation at 6:55 pm from LGD, 10 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.